Align marketplace categories with Codex taxonomy

Constraint: Keep one EAPIL marketplace while using official Codex category metadata and stable plugin IDs.

Rejected: One marketplace per category | Codex groups the UI by marketplace source, which would require users to add multiple markets and change install selectors.

Confidence: high

Scope-risk: moderate

Directive: Keep localized plugins in the same functional category and distinguish them with a language suffix such as -zh.

Tested: Marketplace validation, all manifest/category consistency checks, KeyInfo market tests, frontend lint and production build.

README.md

@@ -17,6 +17,8 @@ codex plugin add <plugin-id>@eapil-skill-market
 
 同一插件的原版与本地化版本可能同时存在。它们的展示名可以相近，但 `plugin-id` 必须不同；安装前应通过列表确认语言版本和精确 ID。
 
+Codex 插件页的大标题按 marketplace 来源分组，不是按插件 `category` 分组。本市场统一使用 Codex 官方分类值；本地化版本与原版放在同一功能分类，并通过 `-zh` 等 ID 后缀和说明文字区分。
+
 安装公共 skill 或第三方 Codex plugin 时也使用同一套命令；具体可安装项以 `codex plugin list --marketplace eapil-skill-market` 的实时输出为准。
 
 有些插件是 skill 集合，安装一个 `plugin-id` 后会同时提供多个 `$skill-name`。可安装项和安装后可用的 skills 均以 Codex 的实际输出为准。